Triethylsilane‐trifluoroacetic acid reduction of hexahydropyrazino[2,1‐c][1,4]oxazine‐6,9‐diones with full control of three stereocenters is reported. The stereoselectivity is completely dependent on the overall conformation of the starting oxazine scaffold. The results prove that triethylsilane can be used for directed enantioselective syntheses of single or fused morpholine‐based heterocycles.

中文翻译：

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使用三乙基硅烷进行烯烃的直接对映选择性还原：完全控制绝对构型的吡嗪并[2,1-c] [1,4]恶嗪-6,9-二酮的合成

据报道，六氢吡嗪并[2,1- c ] [1,4]恶嗪-6,9-二酮在三乙基硅烷-三氟乙酸的还原下可以完全控制三个立体中心。立体选择性完全取决于起始恶嗪支架的整体构象。结果证明，三乙基硅烷可用于基于吗啉的单个或稠合杂环的定向对映选择性合成。